Apparatus for distilling oils



Feb 10, 1931. J. R. SCHONBERG APPARATUS FOR DISTILLING OILS Filed May 28, 1925 2 Sheets-Sheet 1 JACKSON SCHOHBERG. anvefltol Feb. 10, 1931. SCHQNBERG 1,791,937

APPARATUS FOR DISTILLING OILS Filed May 28,, 1925 2 Sheets-Sheet 2 SECTION IIF1G.-1

FIG. 2

FIG. 5

JACKSON scuonszaa Qvwentoz Patented Feb. 10, 1931 UNITED STATES PATENT OFFICE JACKSON R. SCHONBEB'G, OF WESTFIELD, NEW JERSEY, ASSIGNOR TO STANDARD OIL DEVELOPMEN '1 COMPANY, A CORPORATION OF DELAWARE APPARATUS FOR DISTILLING OILS Application filed May 28,

This invention relates to improvements in the art of distilling hydrocarbon oils and will. be fully understood from the following description, taken in connection with the accompanying drawing, in which Fig. 1 is a vertical section through one preferred form of apparatus;

Fig. 2 is a transverse section on line IIII of Fig. 1 i and Fig. 3 is a fragmentary sectional view showing a modification.

Referring to Figs. 1 and 2 of the drawing. reference numeral 1 denotes a furnace setting having burners or other source of heat 2, and a stack 3. Two pairs of horizontal distillation drums, designated 4 and 5, 4 and 5', are mounted in the furnace setting. These pairs of drums are preferably of identical construction and a detailed description of the drums 4 and 5 will therefore sufiice.

Drum 4 is provided with vapor outlet pipes 6 which pass upwardly through the bottom of drum 5, terminating at a point somewhat above its center line. Brickwork or other suitable heat-insulating material 7 covers the top of drum 4 and preferably extends up around the vapor outlet pipes 6 to the hottom of drum 5. The top of drum 5 may be similarly covered by insulation 7'.

Drum 5 is preferably suspended by rods 8 anchored in the roof of the furnace and drum 4 is supported from the bottom of drum 5, as by the flanges 8' about pipes 6.

An oil inlet pipe 9 enters drum 5 and an overflow pipe 10 conveys oil from drum 5 to drum 4. Vapor outlets 11 are provided in drum 5 and may be connected to any desired apparatus for condensation and recovery. For example, the outlets 11 may be connected by a header 12, which is in turn connected to a condenser 13. A vacuum pump 14 is installed in the vapor line leading from the condenser. Manholes 15 provided with suitable closures l6. and draw-off connections 17, are arranged in each drum.

The present invention comprises improvements in the method of heating oil by means of internal flues. In the preferred embodiment shown. the drums are heated by passing hot combustion gases from the burner or fur- 1925. Serial No. 33,358.

nace 2 through a flue 18 extending horizontally throu h drum 4 and through a number of smaller ues 19 similarly arranged in drum 5. The relative heating surface of the flues in the two drums should be so adjusted that the heating will be substantially uniform throughout the oil. In the arrangement shown this is accomplished by the flow of cool feed oil over the extensive heating surface of flues 19.

The. drums are installed centrally in the furnace setting, thus providing chambers 20 and 20 adjacent the ends of the drums. Gases emerging from the flue 18 pass through chamber 20 into the flues 19. From these latter fiues the gases pass into chamber 20 and between the drums to the stack 3. In this way a very complete utilization of the heat of the gases is obtained.

This method of heating oil in a plurality of interconnected drums by countercurrent flow of gases constitutes an important feature of my invention. It enables me to attain a high degree of uniformity of heat in connection with an unusually large area of evaporating surface. The disengaging velocity is therefore low, although the total quantity of vapors evolved is large. For this reason entrainment of oil droplets is minimized and a distillate of good color is assured. Further, direct heating of the shell of the stills by high temperature gases is eliminated, with consequent prevention of local overheating which may be dangerous because of its weakening effect upon the still, or objectionable because of its adverse effect on the oil, or both. It will be noted that the gases passing to the stack have imparted much of their heat to the oil and are therefore at a temperature so low that no damage will be done to the exposed bottom of drum 5. Nevertheless, these gases have a material heating value. Under some circumstances the gases might be hot enough to superheat or otherwise detrimentally affect vapors in drum 4, and its top is therefore insulated, as previously described.

Although it is desirable to provide a number of relatively small heating flues in the upper drum, as this facilitates transfer of heat to the oil, it will be understood that other equivalent arrangements of flues may be made. A plurality of flues may be arranged in the lower drum.

The installation described has important advantages from the construction standpoint. For example, it is practical to use in vacuum distillation relatively small drums without the internal reinforcement which is 'usuall essential in the largedrums now common y employed. The combined vapor disengaging surface of oil, in the small drums may conveniently be made greater than the vapor disengaging surface of a large drum.

When operating according to my invention, entrainment of liquid 'particles is ordinarily small? However, bell-cap plates or other bafile means may be placed over the vapor pipes 6 to prevent any entrainment that may tend to occur, in a manner well understood in the art.

The apparatus described has numerous advantageous uses. It is particularly designed for vacuum distillation, and a process of this type will be described as exemplifying the manner in which the apparatus may be usedl In a typical vacuum distillation process the oil to be distilled is fed in through pipe 9 until the liquid level is above the heating flues in drums 4 and 5. Hot combustion ases are then allowed to pass through the flues in the manner previously described. Owing to the large surface exposed to heat, the oil is rapidly and uniformly heated. Vapors pass up through'pipes 6 into the upper portion of drum 5 and are withdrawn to condensers fractionating means, and the like, which may be of usual type. The degree of vacuum may vary widely in accordance with the particular requirements of the stock being treated. Absolute pressure corresponding to 7 5 mm. or less of mercury are ordinarily satisfactory.

The feed stock may be introduced continuously or intermittently. In general, a continuous feed is preferable. The fresh charge, together with the heavier vapors which may be condensed in the upper drum 5, continuously overflows through pipe 10 into the lower dru'm.

In the form of the invention shown in Fig. 3, the apparatus is so arran ed that vapors ma be takenotf separately rom each drum. This is accomplished by extending the vapor pipe 21 from the lower drum 22 through the vapor pipe 23 of the upper drum 24. Vapors from the lower drum onl may be withdrawn through outlet 25 cont-r0 led by valve 26. By

closing the valve 26 and opening valve 2 in the return bend 28, the vapors from the upper and lower drums may be drawn off together. While entirely separate vapor lines from each drum might be provided, I regard the arrangement shown as more advantageous.

The invention is not limited to the particular form of furnace" illustrated nor to the precise construction or arrangement of the drums or other appurtenances. It will be understood that one or more pairs of drums. may be used and that more than two drums may be arranged in vertical alinement. The pairs. of drums may be operated as'units or they may beinterconnected by suitable pipes. Various other changesmay be made within the scope of the appended claims, in Which it is my intention to claim all novelty inherent in the invention as broadly as the prior art permits.

I claim:

1. Distillation apparatus, comprising two drums, one above the other, heating flues extending through the drums, means for.

passing combustion gases through a flue in one of the drums prior to any substantial.

contact of the gases with outside shells of the drums, then through the flues in the other drum, and finally over the outside shell of the last mentioned drum, the upper drum having an inlet opening for liquid, a pipe for passing liquid from the upper drum to the lower drum, and a vapor line communicating with each drum.

2. Distillation apparatus according to claim 1, in which means is provided for passing the heated gases first through the flue of the lower drum, then through the flues of the upper drum; and finally around the upper drum to a stack.

3. Distillation apparatus, comprising a plurality of drums, one above another, heating flues extending through'the drums, means for passing combustion gases through a flue in one of the drums prior to any substantial contact of the gases with outside shells of the drums, then through flues in another 7 drum and finally in contact with the outside shell of the last mentioned drum, the upper drum having an inlet opening for liquid, a pipe for passing liquid from the upper drum to the lower drum, and a -vapor line coinmunicatin ACKSON R. SCHONBERG.

with at least one of thedrums. A 

